Chilton.- — On some Subterranean Crustacea. 87 



Art. III. — Notes on, and a new Species of- Subterranean Crustacea. 



By Charles Chilton, M.A. 



[Read before the Philosophical Institute of Canterbury, 5th October, 1882.] 



Plate IV. 

 Corrections and Additions to previous Paper.* 

 In my previous paper I have stated that the well from which the Crustacea 

 were obtained was "not more than twenty-five feet deep." I have since 

 found that this is considerably too much, it is really only sixteen or seven- 

 teen feet deep ; sinee then, however, the well has been filled in, so that it 

 is now practically the same as though the pipe had been simply driven into 

 the ground as in an artesian well. 



The Crustacea still continue to come up, though not so frequently as 

 before, and they now vary more, sometimes coming up pretty abundantly 

 while at other times they are very scarce; and while previously Calliope 

 subterranea. (female) used to be much more abundant than any of the other 

 species, it now, though still more abundant than the others, does not pre- 

 ponderate over them nearly so much as before. Next come Crangonyx 

 compactus and Cruregens fontanus which occur in about equal numbers, while 

 Gammarus fragilis is now the rarest of all. 



From another pump about two or three chains from the first, I have 

 obtained a few specimens of Calliope subterranea (female), and from a third 

 pump about a mile and a half distant I got a single specimen of Gammarus 

 fragilis, and I have heard of similar animals being seen from another pump 

 about a mile distant from the first one, but I have not seen specimens from 

 this well. These facts seem to show that the Subterranean Crustacea are 

 fairly well distributed in the district. 



All these wells are sunk in a bed of gravel which lies immediately under 

 the surface soil. Through this gravel water continually percolates, and can 

 always be found at the depth of a few feet from the surface, the depth vary- 

 ing according to the situation, the dryness of the season, the state of the 

 neighbouring River Eyre, etc. I do not think that there is anywhere any 

 large connected quantity of water, but I believe that the Crustacea live in 

 the water which percolates through the interstices between the stones in 

 the bed of gravel. 



With regard to the origin of these Crustacea one can as yet only conjec- 

 ture. Their nearest allies appear to be marine in their habitat. Cruregens 

 fontanus would, but for the absence of the last pah- of thoracic legs, come 

 under the genus Paranthura, the species of which, as well as of the allied 

 genus Anthura, are all marine. Besides Cruregens fontanus, I have obtained 



* " On some Subterranean Crustacea,'" " Trans. N.Z. Inst.," vol. xiv., p. 171. 



